"Microsoft routinely makes small changes to internal components over the lifetime of a product, based on numerous factors including supply chain partnerships, availability, and value for our customers," Microsoft said to CNET in a statement.

For any customers "experiencing...concerns," Microsoft suggests chatting with tech support here.

The Surface Pro 2 is fairly unique (among tablets) in its use of a laptop-class Intel CPU, as CNET Reviews points out. (One of the reasons for the device's relative thickness.)

Microsoft eschewed both Atom processors and power-efficient Y series Core processors in favor of the faster U series.

The Surface Pro 2's performance as tested back in October by CNET got pretty close to the MacBook Air (June 2013) on certain benchmarks.

It should get even closer now with the new 4300U.

Note: I can also confirm that the Surface Pro 2 is shipping with a new processor. The screen shot below is taken from a recently-shipped Surface Pro 2 that I have been using.

Surface Pro 2's new processor. It is now shipping in the latest second-generation Microsoft tablets. This screen capture was taken from a recently-shipped model I am now using.
Brooke Crothers

About the author

Brooke Crothers writes about mobile computer systems, including laptops, tablets, smartphones: how they define the computing experience and the hardware that makes them tick. He has served as an editor at large at CNET News and a contributing reporter to The New York Times' Bits and Technology sections. His interest in things small began when living in Tokyo in a very small apartment for a very long time.
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